|LV= County Championship Division One, Emirates Old Trafford, Manchester (day one)|
|Gloucestershire 252: Harris 67, Dent 52, Higgins 51*|
|Lancashire 3 pts, Gloucestershire 2 pts|
Pakistan paceman Hassan Ali had a home debut to remember in Manchester with 6-47 to bowl out Gloucestershire for 252 before Lancashire closed on 11-1.
Lancashire endured a wicketless morning, including England legend Jimmy Anderson on his first appearance since the fourth Ashes Test in January.
But a 119-run stand from Marcus Harris (67) and Chris Dent (52) was broken by Hassan in the 41st over.
And Gloucestershire collapsed before one shock late run-out scalp in reply.
Off the second ball of the final over, George Balderson fell short answering a run-out call from Luke Wells.
That was at least an uplifting note to end the day on for Gloucestershire, who lunched on 101-0, only to then lose six wickets for just 69 runs, three of them to Ali - with only an unbeaten half-century from Ryan Higgins to cheer them.
Anderson looked understandably rusty as his first seven-over spell went for 21, but he was more like his economic best over his other two spells, in which, although wicketless, he conceded just nine more runs off nine overs.
His England colleague Saqib Mahmood fared slightly better, taking 2-44, with a wicket each for Balderson and leg-spinner Matt Parkinson, despite being hoisted into the stand in his first over by Harris.
Lancashire paceman Hassan Ali:
"It was special for me to be bowling with the great Jimmy Anderson. I will remember coming off the ground and he was clapping me - it was a great moment for me.
"I was nervous about sharing the bowling with Jimmy but he was there to support me and he was backing me. The first session wasn't good enough but, after that, we tried to keep bowling in the right areas.
"I have heard a lot about county cricket and I will try my best to get a lot of experience here - I have Jimmy here and I will speak to him. It is a great opportunity for me. There is a lot of talent in this group. We have a brilliant bowling attack."
Gloucestershire all-rounder Ryan Higgins:
"At the beginning of the day we had two quality batters facing off against some really quality bowlers and it was actually a pleasure to watch and see how those bowlers go about their business.
"Watching James Anderson is always nice. For our openers to get through that was testament to how good they are.
"We all know we didn't play the situation in the afternoon well enough - the ball started reversing a little bit but it wasn't extreme reverse swing. Unfortunately it was enough to do for us in that session."